If you’re using kanban in your environment, you probably use a cumulative-flow diagram. It’s a handy tool to track kanban metrics like cycle time and to quickly see bottlenecks. In addition to all the kanban goodness it gives you, it can also double as a timeline that you can use in your retrospectives.
Whether you use a physical version posted on your kanban board (like my current team does) or an electronic one, you can annotate dates with important events, such as when:
- A team member joins or leaves
- An unexpected technical problem surfaces, like a major refactoring or bug
- The team decides to change something about its kanban, like increase a WIP limit
- The team makes a positive change, like switching pairs more often
It’s pretty easy to do, especially if you have a physical chart that you update during your standup meeting.
Then, when you have a retrospective, bring the diagram along to help you remember what happened during the period over which you’re retrospecting. If you’re anything like the teams I’ve been on and like me, you have a hard time remembering what happened beyond yesterday, so it’s handy to have a reference. Having this time-based information will help you make more objective decisions about how to improve, since you won’t be guessing so much as to why your cycle time lengthened over the last week, or why you decided to decrease a WIP limit a month ago.